19 Dec
2018
19 Dec
'18
3:46 p.m.
On Dec 19, 2018, at 12:11 , Thomas Bellman <bellman@nsc.liu.se> wrote:
On 2018-12-19 20:47 MET, valdis.kletnieks@vt.edu wrote:
There was indeed a fairly long stretch of time (until the CIDR RFC came out and specifically said it wasn't at all canon) where we didn't have an RFC that specifically said that netmask bits had to be contiguous.
How did routers select the best (most specific) route for an address? If the routing table held both (e.g.) 10.20.30.0/255.255.255.64 and 10.20.30.0/255.255.255.32, then 10.20.30.97 would match both, and have the same number of matching bits.
/Bellman
The institution of the longest match rule came with the prohibition (deprecation) of discontiguous net masks. Owen